In the fabrication of mass produced articles requiring assembly of various parts, it is necessary to spot, bore, drill, ream, and countersink great numbers of holes with repeatability and accuracy. Frequently such operations must be performed in thin sections of fiberglass, steel, copper, aluminum, or in metal or plastic tubing. Positioning of these operations is facilitated through the use of specially designed jigs and fixtures, which are frequently equipped with bushings of a diameter appropriate to the tool performing the operation intended at each location. Different tools, often having different diameters must be chucked into the power source, which renders the power source and its operator unproductive during tool changeover. Insertion and withdrawal of the tool from the jig or fixture causes wear of both the tool and the bushing, causing lack of reproducibility and accuracy of the operation, replacement of tools and bushings, scrap and downtime.